New supercharger kit
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From: Cerritos
Originally Posted by slimjim8201,Nov 18 2006, 04:25 PM
There are many differences between the compressors used in the Rotrex systems and the centrifugal systems. Centrifugal compressors are designed to operatate at MUCH lower operating speeds, as there is a limit to how fast the pulley/gear drives can efficiently spin them. For this reason, they have completely different impeller designs and considerable larger housings designed to move more air at a lower operating point.
Turbocharger compressors spin at 2-4 times the speed of most centrifugal compressors. Their compressor housings are a lot smaller for this reason. 500 CFM from a small compressor spinning at 150,000 RPM isn't very different than 500 CFM from a large compressor spinning at 50,000 RPM. The fact that the Rotrex drive spins much faster is not the cause of the more desirable boost curve. That curve is directly related to the fact that the blower speed is not held at a constant ratio relative to engine speed.
If this kit is making only 300 whp at 10 psi, I'd be pretty dissapointed. That must be a misquote.
Turbocharger compressors spin at 2-4 times the speed of most centrifugal compressors. Their compressor housings are a lot smaller for this reason. 500 CFM from a small compressor spinning at 150,000 RPM isn't very different than 500 CFM from a large compressor spinning at 50,000 RPM. The fact that the Rotrex drive spins much faster is not the cause of the more desirable boost curve. That curve is directly related to the fact that the blower speed is not held at a constant ratio relative to engine speed.
If this kit is making only 300 whp at 10 psi, I'd be pretty dissapointed. That must be a misquote.
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From: Slovakian living in Dubai
the only thing that stops me from killing my self and not have waited for this is the fact that I will be hitting the dyno with 16psi tomorrow on my reworked turbo set up. Otherwise I would just hold on to my NA components I had (header, single exhaust ect.) and get this.
I think 300whp @ 10psi is underrated even tho this blower is not as huge as the Vortech. Plus keep in mind you can still make more power by adding a J's Racing header and 70mm single exhaust.
I think 300whp @ 10psi is underrated even tho this blower is not as huge as the Vortech. Plus keep in mind you can still make more power by adding a J's Racing header and 70mm single exhaust.
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From: Alhambra, CA
I must admit that i belong to "daily-driver friendly" group. MPG is a concern. Even if it's a miniscule one, it's still a concern I factor in. Can anyone speculate on any MPG effects for this JR Rotrex?
Obviously, your mileage will vary but in general i'm hoping someone can help a FI noob with some MPG estimates.
Obviously, your mileage will vary but in general i'm hoping someone can help a FI noob with some MPG estimates.
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From: New York
Originally Posted by ryu_2k3,Nov 19 2006, 03:06 PM
I must admit that i belong to "daily-driver friendly" group. MPG is a concern. Even if it's a miniscule one, it's still a concern I factor in. Can anyone speculate on any MPG effects for this JR Rotrex?
Obviously, your mileage will vary but in general i'm hoping someone can help a FI noob with some MPG estimates.
Obviously, your mileage will vary but in general i'm hoping someone can help a FI noob with some MPG estimates.
Joined: Aug 2006
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From: Huntsville, AL
Being that the TB is places after the compressor and there is a blow off/pop off valve there is still a bit of parasitic drag just like a Comptech or Vortech system.
However despite having the blow off/ pop off valve with the JR setup I would assume there would be more drag when out of the throttle due to the speed of the turbine and the head pressure on the out put side. All though its is probably not that much more then the Vortech or the Comptech systems.
However despite having the blow off/ pop off valve with the JR setup I would assume there would be more drag when out of the throttle due to the speed of the turbine and the head pressure on the out put side. All though its is probably not that much more then the Vortech or the Comptech systems.
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From: West Hollywood, CA
If the SC is making ful boost by 2000 rpm.. that means there is alot more force all through out the entire RPM range. Much more wear and tear then making full boost by say 5000 rpm. So does that mean that the engine will wear out that much faster? Just curious if my logic is correct. Personally... If some one were to complain about a 2.2L making 300 whp that "only lasted 95,000 miles" I would say their crazy. Thats a crapload of power from a tiny engine. Allthough technology is making this a fun game of how much power you can make with a tiny engine!!
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From: Alhambra, CA
Originally Posted by NFRs2000NYC,Nov 19 2006, 12:50 PM
IN my experience, as long as you keep your right foot light on the throttle, your MPG should be as good as stock, or 1-2mpg worse. You wont be dipping into the single digits if thats what you are worried about.
On a different note, i'm hoping the inertia from the Rotrex spinning doesn't cause the RPM to hang too long after lifting off the gas pedal. This is probably a non-issue and my guess is it probably has an opposite effect due to parasitic drag.
*eagerly awaits*